The present invention relates generally to the field of beverage dispensing gas pressure systems and in particular to a system and method for detecting a gas leak, actuating an alarm, and activating a backup gas system to continue beverage dispensing operation.
Beverages, such as beer and increasingly, wine, are driven from kegs or other containers to be dispensed from a tap by pressurized gas. Most bars and restaurants maintain at least one large tank of carbon dioxide (CO2), which is necessary to provide carbonated water for a soda machine. Consequently, CO2 gas is often used to pressurize the beer kegs. Pressurizing beer kegs with CO2 injects excessive CO2 gas into the beer, causing excessive foaminess. This effect increases as the volume of CO2 relative to the volume of beer in the keg increases—that is, as the keg empties. In most cases, a bartender will swap out a keg when it is depleted to about 10% of its original volume, rather than waste time at the tap attempting to draw a beer without excessive foam.
Nitrogen gas (N2) is easily filtered from atmospheric air by a N2 generator, and may be stored in a pressurized tank for use in driving beverages to a tap, either alone or in combination with CO2 gas. N2 is an inert gas that contains no oxygen component. Pure N2 is preferred for driving wine, as it disallows oxidation of the wine and inhibits the growth of bacteria.
When beer is driven from kegs to a tap using pure N2, the beer retains only the CO2 resulting from its fermentation process, and is perceived as flat. The beer will contain bubbles, but may not generate a head when poured from the tap. Ideally, beer should be driven by a blend of CO2 and N2 gas to enhance its carbonation, but not pure CO2. Further, the ideal proportion of gases varies by beer.
A known beverage dispensing system includes a N2 generator that generates N2 from atmospheric air as a background activity, and stores the N2 gas in a pressurized container where it is available to drive beverages to taps. The system also connects to one or more conventional CO2 tanks. The system mixes N2 and CO2 gasses in optimal ratios for distribution to beer kegs. For example, most beer requires a 60/40 ratio of CO2 to N2; Guniess® beer requires a ratio of 25/75. The system may dispense pure N2 to drive wine.
Given the large margins in beer sales, eliminating a waste of approximately 10% per keg quickly pays for the lease or purchase of such a system, and thereafter delivers pure profit to the bar or restaurant. Bars and restaurants may purchase blended-gas beverage dispensing systems, or may lease them from a leasing company. In either case, if the system is installed and operated properly, the bar or restaurant, or the leasing company, will realize a normal operating life of the system. If there are fitting or hose leaks in the any portion of the beer dispensing operation, or if a bartender leaves the tap of an empty keg in the open position, the N2 generator may run for excessive hours. This increases the cost of operation through wasted energy costs, and shortens useful life of the system. This results in increased installed cost for the system, borne by the bar or restaurant, or the leasing company, which is responsible for maintaining the system.
Additionally, in the case of leased system, the monthly leasing fee is often determined by the hours of operation of the N2 generator. This practice correlates the lease fees to the actual amount of beer dispensed by the bar or restaurant. In this case, the detection of excess N2 consumption may directly lower the cost of leasing the system.